Surgical Stapler

ABSTRACT

A surgical fastener applying comprising a cartridge section having a cartridge containing a plurality of fasteners, an anvil section having an anvil for receiving the fasteners when advanced from the cartridge, the cartridge and anvil sections clamping tissue therebetween. The first and second cam members are movable within the cartridge section to fire the fasteners. A cam member supporting member fixed within the cartridge section has an upper surface on which the cam members are slidable. The upper surface of the cam member supporting member has a first upper surface portion on a first plane and a second lower surface portion in a different substantially parallel second plane such that the first and second cam members slide in offset planes on the upper surface to fire the fasteners.

This application claims priority from provisional application Ser. No.61/018,685, filed Jan. 3, 2008, the entire contents of which areincorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a surgical stapling device and moreparticularly to a surgical stapling device having pusher-engaging cammembers that are slidable on offset planes.

2. Background of the Related Art

There are several known types of surgical stapling instrumentsspecifically adapted for use in various procedures. In many suchsurgical devices, tissue is first grasped or clamped between opposingjaw structures and then joined by surgical fasteners. The fasteners aretypically in the form of surgical staples. These staples generallyinclude a pair of legs adapted to penetrate tissue and connected by abackspan from which they extend. In use, the staples are formed to a “B”configuration. Two-part fasteners are also known and include legs thatare barbed and connected by a backspan which are engaged and locked intoa separate retainer piece that is usually located in the anvil. In somedevices, a knife is provided to cut the tissue which has been joined bythe fasteners.

In these devices, one of the jaw structures carries a staple cartridgehaving one or more laterally spaced rows of staples, which are alignedwith corresponding rows of anvil depressions on an opposing jawstructure. The tissue is initially gripped or clamped such thatindividual fasteners can be ejected from the cartridge, through theslots, and forced through the clamped tissue. The staples are ejected bylongitudinal movement of a driver and forced through the clamped tissue,forming against the staple forming depressions of the anvil. The staplescan be arranged in a linear or non-linear row.

A common issue in transecting tissue and/or in anastomosis proceduresemploying the surgical stapling instruments is the balance betweenanastomotic strength and the degree of hemostasis achievable. It isknown to include different size staples in a surgical staplinginstrument having a constant gap (uniform distance) between an anvil anda staple cartridge.

A common concern in these surgical procedures is hemostasis, or the rateat which bleeding of the target tissue is stopped. It is commonly knownthat by increasing the amount of pressure applied to a wound, the flowof blood can be limited, thereby decreasing the time necessary toachieve hemostasis. To this end, conventional surgical fasteningapparatus generally apply two or more rows of fasteners about thecut-line to compress the surrounding tissue in an effort to stop anybleeding and to join the cut tissue together. Each of the fasteners willgenerally apply a compressive force to the tissue sufficient toeffectuate hemostasis, however, if too much pressure is applied, thiscan result in a needless reduction in blood flow to the tissuesurrounding the cut-line. Accordingly, the joining of tissue together inthis manner may result in an elevated level of necrosis, a slower rateof healing, and/or a greater convalescence. On the other hand, if notenough pressure is applied, proper hemostasis may not be achieved.

Consequently, it would be advantageous to provide a surgical fasteningapparatus capable of limiting the flow of blood in the tissueimmediately adjacent the cut tissue to effectuate hemostasis and woundclosure, while maximizing blood flow in the surrounding tissue tofacilitate healing.

SUMMARY

The present disclosure relates to forming different sized staples byadvancing cam members on different planes. In preferred embodiments, thecam members have common sizes and angles and the pushers have commonsizes and angles which among other advantages, can facilitate themanufacturing process.

More specifically, a cartridge section having offset or stepped surfacesfor cam members to travel along is disclosed herein. The offset orstepped surfaces allow the cam members to travel in different planes,which enables in preferred embodiments cam members of substantially thesame height and pushers of substantially the same height to be used tofire staples of different sizes against an anvil.

In one aspect, the present disclosure provides a surgical fastenerapplying apparatus comprising a cartridge section having a cartridgecontaining a plurality of fasteners and an anvil section having an anvilfor receiving the fasteners when advanced from the cartridge, thecartridge and anvil sections clamping tissue therebetween. First andsecond cam members are movable within the cartridge section to fire thefasteners. A cam member supporting member is fixed within the cartridgesection and has an upper surface on which the cam members are slidable.The upper surface of the cam member supporting member has a first uppersurface portion on a first plane and a second lower surface portion on adifferent substantially parallel second plane such that the first andsecond cam members slide in offset planes on the upper surface to firethe fasteners.

In a preferred embodiment, the first and second cam members are ofsubstantially the same height. In a preferred embodiment, the pluralityof fasteners include a first set of fasteners having legs of a firstlength and a second set of fasteners having legs of a second longerlength.

In a preferred embodiment, the first upper surface portion is closer tothe anvil section than the second lower surface portion, and the secondcam member slides along the second lower surface to fire the second setof fasteners.

The cartridge may include third and fourth cam members, the third andfourth cam members being movable on substantially parallel offsetplanes. The second and fourth cam members are preferably positionedoutboard of the first and third cam members and configured to firefasteners having a length greater than a length of fasteners fired bythe first and third cam members.

In one embodiment, the cartridge includes a plurality of fastenerpushers configured to engage the fasteners as they are advanced by thecam members, the fastener pushers preferably being of substantially thesame height. The pushers are preferably movable by the cam members in adirection substantially transverse to the direction of movement of thecam members.

The present disclosure also provides a surgical fastener applyingapparatus comprising a cartridge section having a cartridge containingfirst and second sets of fasteners and an anvil section having an anvilfor receiving the fasteners when advanced from the cartridge, thecartridge and anvil sections clamping tissue therebetween. A first cammember is movable within the cartridge section to advance the first setof fasteners against the anvil to fully form the fasteners, the firstcam member movable in a first plane. A second cam member is movablewithin the cartridge section along with the first cam member to advancethe second set of fasteners to fully form the fasteners, the second cammember movable in a second plane offset from the first plane and furtherfrom the anvil section than the first plane when the anvil and cartridgesections are positioned to clamp tissue therebetween.

In one embodiment the cam members are of substantially the same height.In one embodiment, the first set of fasteners has legs of a first lengthand the second set of fasteners has legs of a second longer length.

Preferably, the cartridge includes a plurality of fastener pushersconfigured to engage the fasteners as they are advanced by the cammembers, the fastener pushers preferably being of substantially the sameheight.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described hereinbelowwith references to the drawings, wherein:

FIG. 1 is a view in partial cross-section showing the cams bars ondifferent planes.

FIG. 2 is a perspective view of two cam bars and two staple pushers ofFIG. 1;

FIG. 2A is a perspective view of a portion of the cam bars and cam barsupport separated from the supporting channel;

FIG. 3 is a perspective view of one embodiment of a surgical staplerhaving the offset cam bars of FIG. 1;

FIG. 4 is a perspective view of the surgical stapler of FIG. 3 with theanvil and cartridge assemblies separated;

FIG. 5 is a perspective of an alternate embodiment of a surgical staplerof the present disclosure having offset camming members; and

FIG. 6 is an exploded perspective view of the distal portion of thesurgical stapler of FIG. 5.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed stapler will now be described indetail with reference to the drawings wherein like numerals designateidentical or corresponding elements in each of the several views. As iscommon in the art, the term “proximal” refers to that part or componentcloser to the user or operator, i.e. surgeon or physician, while theterm “distal” refers to that part or component further away from theuser.

FIGS. 1 and 2 illustrate a first embodiment of the cam bar/pusherarrangement of the present disclosure. FIGS. 3 and 4 illustrate one typeof surgical stapler that can incorporate the cam bar/pusher arrangementof FIG. 1.

Turning first to FIGS. 3 and 4, the stapler 10 has a cartridge receivinghalf section 12, an anvil half section 14, and handles 48 and 50 forfacilitating clamping of the sections 12 and 14. Cartridge half section12 has a channel 18 (FIG. 2A) to receive cartridge assembly 16 whichincludes a plurality of staples 130 and a plurality of pushers 120 toadvance the staples 130 from the cartridge 19 through slots 23. A cambar assembly is advanced by distal advancement of manual firing lever56. The cam bar assembly is slidable on cam bar supporting member 150for longitudinal advancement in the cartridge 19 to advance the pushers120 in a direction substantially transverse to the longitudinal axis ofthe stapler and substantially transverse to the direction of movement ofthe cam bars. Engagement of the pushers 120 by the cam members advancesthe staples 130 through the tissue and into contact with the anvildepressions of the anvil half section 14. Preferably there are twostaggered rows of slots 23 formed on either side of a slotted knifetrack in the cam bar assembly which guides a knife between the rows ofstaples. A single staple is positioned in each of the slots 23. Staplepushers 120 are aligned with each slot 23 so that a single staple pusheris positioned under the staple retained in the slot. The pushers canoptionally be attached to each other in groups of two offset orientedpusher pairs. More details of the stapler are disclosed in commonlyassigned U.S. Pat. No. 7,140,527, issued Nov. 28, 2006, and U.S. Pat.No. 7,055,730, issued Jan. 6, 2006, the entire contents of each of theseapplications is incorporated herein by reference.

With reference to FIGS. 1 and 2 illustrating the cam member arrangementof the present disclosure, the pushers 120 are advanced by the cammingsurfaces 112 a, 112 b of cam members 110 a, 110 b which as shown are inthe form of cam bars 110 a, 110 b. FIG. 2 illustrates a distal portionof two of the cam bars 110, 110 b and two of the pushers 120 a, 120 b;FIG. 1 illustrates four cam bars (110 a-110 d) and four of the pushers120 a-120 d. The camming surfaces 112 a, 112 b are preferablylongitudinally staggered with respect to each other to distribute thefiring forces

More specifically, four cam bars (members) 110 a-110 d, four pushers 120a-120 d and four staples 130 a-130 d are shown in FIG. 1. The cam bars110 a-110 d are preferably of substantially the same size (height) andangle. The staple pushers 120 a-120 d are also preferably ofsubstantially the same size (height). Cartridge half section 12 alsoincludes a cam bar (member) supporting member 150 fixedly mounted withinchannel 18 and having an offset plane 151 on its upper surface. Theupper surface includes a lower surface portion 152 and a substantiallyparallel upper surface portion 154 on each side of the longitudinalcenterline and which form surfaces on which the respective cam bars(members) 110 a-110 d slide distally to sequentially fire a longitudinalrow of staples contained in the staple cartridge 19. As shown, cam bar110 a is positioned on (and slidable longitudinally along) lower surfaceportion 152 of offset plane 151 and is in contact with pusher 120 a,which contacts staple 130 a. Cam bar 110 b is positioned on (andslidable longitudinally along) upper surface portion 154 of offset plane151 and is in contact with pusher 120 b, which contacts staple 130 b.Similar to cam bar 110 b, cam bar 110 c is positioned on upper surfaceportion 154; similar to cam bar 110 a, cam bar 110 d is positioned onlower surface portion 152 to contact respective pushers 120 c, 120 d tofire staples 130 c, 130 d. Thus, cam bars 110 a and 110 d are outboardof cam bars 110 b, 110 c.

As can be appreciated with reference to the Figures, the difference inheights of surface portions 152, 154 of offset plane 151 enables staples130 of different sizes (leg lengths) to be fired into anvil pockets ofanvil assembly 14 (shown schematically in FIG. 1) for formation by theanvil. Accordingly, the staples of smaller sizes (130 b and 130 c) arealigned with cam bars 110 b and 110 c, respectively, on upper surfaceportion 154. The staples of larger sizes (130 a and 130 d) are alignedwith cam bars 110 a and 110 d, respectively, on lower surface portion152. It is envisioned in a preferred embodiment that the heightdifference “d1” between surface portions 152 and 154 of offset plane 151is approximately twice the height difference “d2” between larger staples(130 a and 130 d) and smaller staples (130 b and 130 c). Other heightdifferences are also contemplated. Preferably, the smaller staples arein the inside rows and the larger staples are in the outside rows. Inthis manner, the longer staples are provided on the outer rows where thetissue might be thicker as a result of clamping by the instrument jaws(anvil and cartridge) as some of the fluid of the tissue is squeezed outso that the tissue is compressed further at the center portions of thecartridge and anvil than at the lateral edges, thereby leaving thickertissue at the edges. In this manner, the stapler is capable of limitingthe flow of blood in the tissue immediately adjacent the cut tissue toeffectuate hemostasis and wound closure, while maximizing blood flow inthe surrounding tissue to facilitate healing.

It should be appreciated that the offset planes of the presentdisclosure can also be used with other staplers, including, for example,other linear staples and endoscopic linear staplers, such as disclosedfor example in FIG. 5 described below.

It is also contemplated that as an alternative to two surface heights ofthe cam member support 150 (or support 240 described below), more thantwo surface heights can be used. For instance, the offset planes caninclude surfaces of three different heights to provide advancement ofcam members at three different levels. This can be used, for example,for applying three different size staples.

A method of firing staples of different sizes is also provided. Themethod includes causing first and third cam members (bars) 110 b, 110 cto travel along a first plane and causing second and fourth cam members(bars) 110 a, 110 d, outboard of the first and third cam members 110 b,110 c, to travel along a second plane, where the first plane and thesecond plane are offset from each other. The second plane is furtherfrom the anvil surface when the cartridge 19 and anvil are in positionclamping tissue therebetween. As the cam bars 110 a-110 d travel alongthe upper surface of cam member support 150, they contact respectivepushers which then drive the respective staples out of the correspondingcartridge slot, through tissue clamped between the anvil and cartridge,and into anvil pockets for formation into B-shaped staples. This methodapplies staples of different lengths. For example, staples of shorterlength would be applied to clamped tissue closer to the center of thejaws and staples of longer length would be applied to clamped tissuefurther from the center.

In a preferred embodiment, the raised (stepped) surfaces for supportingthe cam bars cam can be formed on a plastic or other material insert inthe bottom of channel 18 of the cartridge half section 12. The insertcan be one piece formed with surfaces on different planes, e.g. byvarying the thickness of the portions, or, alternatively, separateinserts to achieve the differing heights can be utilized.

FIGS. 5 and 6 illustrate an alternate embodiment utilizing the conceptof cam members on offset planes. Six camming members 206 a-206 e areillustrated, attached together, with the two outer cam members on eachside advanceable along one plane and the two middle cam membersadvanceable along a higher plane. More specifically, camming members 206a, 206 b, 206 e and 206 f form the two outer rows of the cam barassembly on each side of a longitudinal axis of the assembly. Cammembers 206 c and 206 d are positioned in the middle (between the twoouter rows) and configured for firing the two inner rows of staples. Acam member support 240 has an upper surface with an offset plane 241such that it is stepped as shown to provide substantially paralleloffset planes to offset the height of the two inner cam members 206 c,206 d from the four outer cam members 206 a, 206 b, 206 e, 206 f. Morespecifically, cam member supporting member 240 is fixedly positionedwithin channel 230 of cartridge assembly 220 and its upper surfaceincludes first and second lower surface portions 242, 244, and anintermediate upper surface portion 246 in between. The intermediatesurface portion 246 has a raised surface such that it is higher, e.g.closer to the anvil assembly 214 when the instrument is clamped, thanthe outer lower surface portions 242, 244. The higher positioned cammembers 206 c, 206 d slide along the raised intermediate surface portion246. The cam bars slide distally to sequentially advance staple pushersin a direction substantially transverse to the movement of the cammembers 206 a-206 f to fire longitudinal rows of staples contained incartridge 227 through the tissue and against anvil member 225 to formthe staples. In a preferred embodiment, the staples having legs ofshorter length are fired by intermediate cam members 206 c, 206 d andthe larger staples having legs of longer length are fired by the outerset of cam members 206 a, 206 b, 206 e, and 206 f. The outer surfaceportions 242 and 244 of offset plane 241 are lower, e.g. further fromthe anvil assembly 214 when the instrument is clamped, to accommodatethe outer cam members 206 a, 206 b, 206 e, 206 f to fire staplers oflonger length than the length of the staples in the inner rows.

This cam arrangement can be used with the endoscopic surgical stapler ofFIG. 5, which has an elongated tubular portion 212, an anvil assembly214 pivotally mounted at a distal end portion of the elongated tubularportion 212 and a cartridge assembly 220. The anvil and cartridgeassemblies 214, 220 are moved into approximation to clamp tissuetherebetween. A handle 230 is squeezed to clamp the anvil and fire thestaples in the manner disclosed in U.S. Pat. No. 5,762,256 issued Jun.9, 1998 and U.S. Pat. No. 5,865,361 issued Feb. 2, 1999, the entirecontents of which are incorporated herein by reference.

In a preferred embodiment, staples of longer leg length are placed inthe four outer rows and staples of shorter leg length are placed in thetwo inner rows. Preferably, the cam members are of substantially thesame height, as are the pushers.

Although described for fastener applying apparatus for firing staplesformed by an anvil, the offset plane of this disclosure could also beused in fastener applying apparatus for firing two part fasteners.

While the above description contains many specifics, these specificsshould not be construed as limitations on the scope of the presentdisclosure, but merely as illustrations of various embodiments thereof.Therefore, the above description should not be construed as limiting,but merely as exemplifications of various embodiments. Those skilled inthe art will envision other modifications within the scope and spirit ofthe disclosure.

1. A surgical fastener applying apparatus comprising a cartridge sectionhaving a cartridge containing a plurality of fasteners; an anvil sectionhaving an anvil for receiving the fasteners when advanced from thecartridge, the cartridge and anvil sections clamping tissuetherebetween; first and second cam members movable within the cartridgesection to fire the fasteners; and a cam member supporting member fixedwithin the cartridge section and having an upper surface, the cammembers slidable along the upper surface, the upper surface of the cammember supporting member having a first upper surface portion on a firstplane and a second lower surface portion in a different substantiallyparallel second plane such that the first and second cam members slidein offset planes on the upper surface to fire the fasteners.
 2. Thesurgical fastener applying apparatus as recited in claim 1, wherein thefirst and second cam members are of substantially the same height. 3.The surgical fastener applying apparatus of claim 2, wherein theplurality of fasteners include a first set of fasteners having legs of afirst length and a second set of fasteners having legs of a secondlonger length.
 4. The surgical fastener applying apparatus of claim 1,wherein the plurality of fasteners include a first set of fastenershaving legs of a first length and a second set of fasteners having legsof a second longer length.
 5. The surgical fastener applying apparatusof claim 4, wherein the first upper surface portion is closer to theanvil section than the second lower surface portion, the second cam barslides along the second lower surface to fire the second set offasteners.
 6. The surgical fastener applying apparatus of claim 1,wherein the cartridge includes third and fourth cam bars, the second andfourth cam bars being movable on offset planes, the second and fourthcam bars positioned outboard of the first and third cam bars.
 7. Thesurgical fastener applying apparatus of claim 1, wherein the second andfourth cam bars are configured to fire fasteners having a length greaterthan a length of fasteners fired by the first and third cam bars.
 8. Thesurgical fastener applying apparatus of claim 1, wherein the first andsecond upper surface portions are formed by varying a thickness of thecam bar supporting member.
 9. The surgical fastener applying apparatusof claim 3, wherein the cartridge includes a plurality of fastenerpushers configured to engage the fasteners as they are advanced by thecam bars, the fastener pushers being of substantially the same height.10. The surgical fastener applying apparatus as recited in claim 9,wherein the first and second cam bars are of substantially the sameheight.
 11. The surgical fastener applying apparatus of claim 9, whereinthe pushers are movable by the cam bars in a direction substantiallytransverse to the direction of movement of the cam bars.
 12. Thesurgical fastener applying apparatus of claim 11, wherein the first andsecond cam members are attached and move as a single unit.
 13. Asurgical fastener applying apparatus comprising a cartridge sectionhaving a cartridge containing first and second sets of fasteners; ananvil section having an anvil for receiving the fasteners when advancedfrom the cartridge, the cartridge and anvil sections clamping tissuetherebetween; a first cam member movable within the cartridge section toadvance the first set of fasteners against the anvil to fully form thefasteners, the first cam member movable in a first plane; and a secondcam member movable within the cartridge section along with the first cammember to advance the second set of fasteners to fully form thefasteners, the second cam member movable in a second plane offset fromthe first plane and further from the anvil section than the first planewhen the anvil and cartridge sections are positioned to clamp tissuetherebetween.
 14. The surgical fastener applying apparatus of claim 13,wherein the cam members are of substantially the same height.
 15. Thesurgical fastener applying apparatus of claim 13, wherein the first setof fasteners has legs of a first length and the second set of fastenershas legs of a second longer length.
 16. The surgical fastener applyingapparatus of claim 13, wherein the cartridge includes a plurality offastener pushers configured to engage the fasteners as they are advancedby the cam bars, the fastener pushers being of substantially the sameheight.
 17. The surgical fastener applying apparatus of claim 15,wherein the cartridge includes a plurality of fastener pushersconfigured to engage the fasteners as they are advanced by the cam bars,the fastener pushers being of substantially the same height.